968Forums.com

Somehow I had missed this thread earlier (incredible, given how addicted I am to this site). Sounds like a great mod - looking forward to adding it, as every bit of heat deflection is a good thing.

lol - well, that's what happens if all you do is hit "view new posts" - that feature does NOT show everything - i am constantly finding things that slip through

Guilty as charged. I've read through the site tutorial, but I didn't see anything that presented a good alternative to the "view new posts" button for quickly, well, viewing the new posts. Any suggestions, or experiences from the members, would be welcomed. Thanks.

there isn't anything any better, short of going category by category - not sure what the problem is, but there is definitely a gap in the capabilities of the search tool, which is what "view new posts" uses



back to the topic at hand, yes, heat deflection is a good thing, if nothing else, it will help to increase the lifespan of a couple of critical items poorly placed by porsche, namely the heater control valve and hall sensor

the sheet metal is in



final check test fit done



instructions written



packing up this afternoon for shipping to pete tomorrow



WOOHOO!

[quote name='flash' post='63305' date='Nov 20 2008, 03:00 PM']the sheet metal is in



final check test fit done



instructions written



packing up this afternoon for shipping to pete tomorrow



WOOHOO![/quote]



Now can we have a picture? <img src="/forum/images/smilies/968/wink.gif" class="smilie" alt="" />

lol - as soon as the description and pic, as well as the pricing, is posted on pete's site, yes



sorry it took so long to get this done - working out the correct angles, bends, etc and getting the ridiculously expensive heat material to stay put was a bit more "interesting" of a problem than i first thought - my first prototype worked fine, but i just thought i could do better - basically i kept "fiddling" with it, making one improvement after another, until i thought i nailed it - i threw away quite a bit more stuff working this one out than i intended - oh well



anyway, i'm sure pete will have this up very quickly - this is one that many people wanted

Bob-



Are there any known, perceived and/or potential issues with installing this? For instance, over-oiling of the K&N filter can lead to fouling of the MAF unit. Any such things that you have been able to discern with the heat shield?



Thanks, as always, for your continued focus on goodies for the 968!



Jim

not that i could think of



the tiptronic cars have something like this already - they did that to create a barrier between the exhaust and the transmission cooling line



i just took their lead, and made it a bit better

This really is a great idea. Ship one to me, too, along with the short-shift kit when it's ready. <img src="/forum/images/smilies/968/wink.gif" class="smilie" alt="" />

Not to take the wind out of anyone's sails - after the install I'd suggest keeping an eye on cabling and hoses located above the edge of the plate. Generally a plate [depending on design] may re-direct the heat to an undesirable location. Or it may imped intended flow through the engine compartment when the car is driven. Heated air will rise even if it has to go around a plate. There may be no issue at all - my point is just to keep an eye on heat sensitive components.



In racing plates may be used to direct heat away from an underhood air intake atop a carburated engine. Fortunately the 68 gets cool air from the front and the manifold is on the opposite side away from the heat. If the car is moving heat shouldn't be an issue. It would be interesting to monitor the temp of the intake system while idling with & w/o the plate.

yeah - done it - i have had the prototype on the car for a long time now for exactly that reason - i wanted to make sure i wasn't wasting my time, or worse, creating a whole new problem - no issues whatsoever, and i have the most likely candidate for a problem with the plastic covers - the only things anywhere near the shield are things that we want protected by it



i did measure intake temps, as well as other temps in the engine bay (i love that new laser gadget) - at idle, sitting still, it certainly is not nearly as effective as when you are moving, or even the fans are turning, but still it does make a difference - i only let it heat soak for a couple of minutes though, so i imagine that if you left it long enough, everything would be the same temp.................until you started moving again

ok - the first batch is on the way to pete - he should be posting the picture, details and pricing any day now

To get more accurate temperature mapping you'd have to run a couple of strategically placed TC's [thermocouples] under a closed hood and monitor the temp in both static and dynamic modes.

I briefly saw your prototype earlier and it'll be interesting to see how it has evolved...

lol - yeah - i sort of did that - i have a few different thermometers of different types around here for just that reason - remember that i have also been playing around with redirection of airflow under the hood for the same reasons



as i said, while there is still an effect while idling and sitting still, as you can imagine, it isn't nearly as much as while moving - it's similar to what the other heat shields do when you are sitting still - that does not mean that they are not effective while air is moving



the last development, besides adding the barrier material that wasn't there when you saw the first of 4 prototypes, was to add a deflector to direct the air that comes in from the headlight bucket area downward and over the manifold and then out the rear of the car



pop on down on the 6th for the gathering and the game and check it out

Are the underhood temperature issues you've been addressing unique to this car, or are they typical for most cars with relatively high specific power? I had never heard of this being a big issue before. Is the 968 worse in this respect than other cars you've worked on?

High underhood temps are not good on any car- I wrapped the turbo on my Race car to reduce underhood temps at the injectors and had a dramatic drop in coolant temp. The turbo runs cooler than my NA Firehawk.

I also made a heat shield a year ago similar to Bob's-Ok he really copied mine, for the turbo to reduce temps at the injectors again. I used the NACA duct to force cool air under the shield. Race car stuff.

Getting back to whether the heat shield affects our car I would say yes. Anything to keep the intake maifold cooler helps with power. Ask me how I know this!!!!

Pete

for me, it wasn't so much a problem as it was just wanting to make things better



the only real "problem" was the illogical factory placement of the heater control valve and hall sensor that are frequently victims of the heat from the exhaust manifold directly below it



but, as pete says, lower intake temp is better - control the exhaust heat and you lower the under hood temps - do that and you have less heat soak in the intake



remember, every 10 degrees of intake temp drop is about 1 hp



with hyundai coming out with an over 300 hp econobox, i'll take those ponies anywhere i can get them



so, anything i can do to help that along............

That's why I suggested a temp differential test while the car is moving. With respect to the position of the exhaust relative to the intake, I doubt there's much heat radiation unless there's heat soak in traffic. And, obviously In traffic, hp isn't a top concern. If anything the heat coming from the radiator, [upstream of the manifold] probably has a greater influence. Most likely there's ~200 deg. air flooding the engine compartment that flows down along the firewall taking the exhaust heat with it. Again, testing would be needed to validate this theory.

I suppose on a tight DE course where air flow is reduced, the underhood temp would increase. And, if so, it may also be worth it to wrap the fuel lines with a foil backed insulator or at least foil [with the shiny side out] - both cool fuel and cool air affect hp...

yup - that's why the mods i've done in the engine bay have worked so well - i have another one happening soon that will seriously reduce intake temps



funny you should mention the fuel thing - i have something in mind there too